Field of the Invention
The present invention relates to a wireless power transfer and charging system and a method for the same, especially to a wireless power transfer and rapid charging system with maximum power tracking and a method for the same that carry out wireless charging in different environments. An optimal transfer frequency is found, the system provides longer transmission distance, reduced output impedance, greater wireless transmission efficiency, and higher speed of wireless charging.
Descriptions of Related Art
Wireless charging is also called inductive charging or non-contact inductive charging. Energy is transferred from a charger to a device by near-field induction (inductive coupling). The device uses the energy received for its own operation and charging of the battery. No physical wire connection is required between the charger and the device. Thus there is no contact metal exposed outside for the charger and the device. This is more convenient in use.
The wireless charging is based on electromagnetic induction. Generally a wireless charger includes a coil that creates an alternating electromagnetic field after being driven by alternating current while another coil in a device takes power from the electromagnetic field and converts it back into electrical current. The electrical current is used for charging the battery and supplying power to the device.
However, the wireless charging system with the expected functions also has shortcoming in practice such as limited transmission range, poor transmission efficiency, limited wireless environment, etc.
Thus there is room for improvement and a need to provide a wireless power transfer and rapid charging system and a method for the same that overcomes the shortcomings of conventional wireless charging devices.